Monoazo dyes containing a fluorosulphonyl group and use thereof

ABSTRACT

Monoazo dyes having formula (1) ##STR1## wherein Q is --Br or --Cl; R 1  and R 2  each independently is H or is selected from the group consisting of C 1-6  -alkyl and aryl groups, each of which may be unsubstituted or substituted by one or more nonionic substituents; and R 3 , R 4 , R 5  and R 6  each independently is H, F, Cl, Br, I, --SO 2  F or an organic moiety selected from the group consisting of C 1-6  -alkyl, C 1-6  -alkoxy, C 1-4  alkanoylamino, --NHSO 2  alkyl, --NHCOC 1-4  alkyl and --Ophenyl moieties, each organic moiety being unsubstituted or substituted by one or more nonionic substituents are provided. The dyes can be employed for the colouring of synthetic textile material.

This invention relates to azo dyes and more particularly towater-insoluble monoazo dyes containing the fluorosulphonyl group, to amethod for their prepharation and to their use for colouring synthetictextile and other materials.

Our International patent application published as WO 95/20014 describesazo compounds which contain at least one fluorosulphonyl group and arefree from water-solubilising groups. The use of these compounds forcolouring synthetic textile materials and for the mass coloration ofplastics is also described.

It has now been found that certain dyes falling within the general classdescribed in WO 95/20014 but not specifically disclosed therein exhibitadvantageous properties when applied as disperse dyes to synthetictextile materials.

Thus, according to the invention, there are provided monoazo dyes whichare free from water-solubilising groups and have the formula: ##STR2##wherein: Q is --Br or --Cl;

R¹ and R² each independently is H or is selected from the groupconsisting of C₁₋₆ -alkyl and aryl groups, each of which may beunsubstituted or substituted by one or more nonionic substituents; and

R³, R⁴, R⁵ and R⁶ each independently is H, F, Cl, Br, l, --SO₂ F or anorganic moiety selected from the group consisting of C₁₋₆ -alkyl, C₁₋₆-alkoxy, C₁₋₄ alkanoylamino, --NHSO₂ alkyl, --NHCOC₁₋₄ alkyl and-Ophenyl moieties, each organic moiety being unsubstituted orsubstituted by one or more nonionic substituents.

Water solubilising groups which must be absent from the dyes of Formula1 particularly include --SO₃ H, --CO₂ H, --PO₃ H and quaternary ammoniumgroups and salts thereof.

When either or both of R¹ and R² represents a C₃₋₆ alkyl group, thealkyl group can be linear or branched, and when branched, the branchingmay form a secondary or tertiary group. One or two points of branchingmay be present. The C--N bond can be formed between the N atom and anycarbon in R¹ or R².

When either or both of R¹ and R² represents an aryl a group, the arylgroup may be phenyl or naphthyl group, which may be substituted at anyposition relative to the bond to the N atom. When either or both of R¹and R² represents a phenyl group, any substituents are preferablypresent ortho and/or para to the phenyl- N bond. In certain embodiments,R¹ and R² may be fused to form, together with the N atom, an aromatic orconjugated heterocyclic group, particularly one comprising a 5 or 6membered ring, or a saturated heterocyclic group, particularly onecomprising a 5, 6 or 7 membered ring.

The optional nonionic substituents for groups represented by R¹ to R⁶particularly include --CN, --OH, --OC₁₋₆ -alkyl, --OCOC₁₋₆ -alkyl,--COOC₁₋₆ -alkyl, phenyl, phenoxy, --OCOphenyl, --OCOphenylSO₂ F,phenylSO₂ F, --OphenylSO₂ F, --CO₂ phenylSO₂ F, --COOC₁₋₆ -alkylOCOC₁₋₆-alkyl and --COOC₁₋₆ -alkylCOOC₁₋₆ -alkyl.

A preferred sub-group of the dyes of Formula 1comprises compounds of theformula: ##STR3## wherein Q is as defined above and each of R¹ and R²,independently, is optionally substituted C₁₋₆ -alkyl.

Within the sub-group of Formula 2, particular mention may be made ofdyes in which each of R¹ and R² is optionally substituted ethyl, forexampie dyes in which R¹ is --C₂ H₅ and R² is --C₂ H₄ X wherein X isselected from --H, --CN, --COOC₂ H₅, --OCOCH₃ and --OC₆ H₅.

The dyes of Formula 1 may be prepared by diazotising6-bromo-2,5-dichloro4-fluorosuiphonylaniline or2,3,6-trichloro-4-fluorosulphonylaniline and coupling the resultingdiazo compound with an aromatic amine of the formula: ##STR4## whereinR¹ to R⁶ are as hereinbefore defined.

The diazotisation and coupling reactions may be performed usingconditions conventionally employed for the type of reactant involved.Typically, the 6-bromo-2,5-dichloro4-fluorosulphonylaniline or2,3,6-trichioro-4-fluorosulphonylaniline may be diazotised in an acidicmedium, such as acetic, propionic or hydrochloric acid using anitrosating agent such as nitrosylsulphuric acid, sodium nitrite ormethyl nitrite at a temperature from -10° C. to 10° C. Coupling with thearomatic amine of Formula 3 may be achieved by adding the diazotised6-bromo-2,5-dichloro-4-fluorosulphonylaniline or diazotised2,3,6-trichloro4-fluorosulphonylaniline to the amine of Formula 3 in analkanol such as methanol at a temperature from 0° C. to 10° C. Aftercoupling, the compound of Formula 1 may be recovered from the reactionmixture by any convenient means such as by filtration.

The 6-bromo-2,5-dichloro-4-fluorosulphonylaniline and2,3,6-trichloro-4-fluorosulphonylaniline, respectively, may be obtainedby bromination or chlorination of 2,5-dichloro-4-fluorosulphonylaniline.

The azo compounds of Formula 1 are useful as disperse dyes and arevaluable for colouring synthetic textile materials and fibre blendscontaining such materials.

The synthetic textile material may be selected from secondary celluloseacetate, cellulose triacetate, polyamide, polyacrylonitrile and aromaticpolyester. The synthetic textile material is preferably polyamide suchas polyhexamethylene adipamide or aromatic polyester, especiallypolyethylene terephthalate. Fibre blends may comprise mixtures ofdifferent synthetic textile materials or mixtures of synthetic andnatural textile materials. Preferred fibre blends include those ofpolyester-cellulose such as polyester-cotton. The textile materials orblends thereof may be in the form of filaments, loose fibres, yarn orwoven or knitted fabrics.

The azo compounds of Formula 1 or mixtures thereof, optionally inconjunction with other disperse dyes, may be applied to the synthetictextile materials or fibre blends thereof by processes which areconventionally employed in applying disperse dyes to such materials andfibre blends.

Suitable process conditions include the following:

i) exhaust dyeing at a pH of from 4 to 6.5, at a temperature of from125° C. to 140° C. for from 10 to 120 minutes and under a pressure offrom 1 to 2 bar, a sequestrant may be optionally added;

ii) continuous dyeing at a pH of from 4 to 6.5, at a temperature of from190° C. to 225° C. for from 15 seconds to 5 minutes, a migrationinhibitor may optionally be added;

iii) printing direct at a pH of from 4 to 6.5, at a temperature of from160° C. to 185° C. for from 4 to 15 minutes for high temperaturesteaming, or at a temperature of from 190° C. to 225° C. for from 15seconds to 5 minutes for bake fixation with dry heat or at a temperatureof from 1 20° C. to 140° C. and 1 to 2 bar for from 10 to 45 minutes forpressure steaming, wetting agents and thickeners (such as alginates) offrom 5 to 100% by weight of the dye may optionally be added;

iv) discharge printing (by padding the dye on to the textile material,drying and overprinting) at a pH of from 4 to 6.5, migration inhibitorsand thickeners may optionally be added;

v) carrier dyeing at a pH of from 4 to 6.5, at a temperature of from 95°C. to 100° C. using a carrier such as methylnaphthalene, diphenylamineor 2-phenylphenol, sequestrates may optionally be added; and

vi) atmospheric dyeing of acetate, triacetate and nylon at a pH of from4 to 6.5, at a temperature of 85° C. for acetate or at a temperature of90° C. for triacetate and nylon for from 15 to 90 minutes, sequestrantsmay optionally be added.

In all the above processes, the compound of Formula 1 or mixture thereofmay suitably be applied as a dispersion comprising from 0.001% to 4% byweight of the azo compound or mixture thereof in aqueous medium.

The dye dispersions may further comprise ingredients conventionally usedin coloration applications such as dispersing agents, for examplelignosulphonates, naphthalene sulphonic acid/formaldehyde condensates orphenol/cresol/sulphanilic acid/formaldehyde condensates, surfactants,wetting agents such as alkyl aryl ethoxylates which may be sulphonatedor phosphated, inorganic salts, de-foamers such as mineral oil ornonanol, organic liquids and buffers. Dispersing agents may be presentat from 10% to 200% on the weight of the azo compound of Formula 1.Wetting agents may be used at from 0% to 20% on the weight of the azocompound of Formula 1.

Suitable dispersions may be prepared by bead milling the compound ofFormula 1 with glass beads or sand in an aqueous medium.

The compounds of Formula 1 provide synthetic textile materials withyellow-brown colorations exhibiting good fastness to washing, light andheat.

The azo compounds of Formula 1 are also useful for the mass colorationof plastics materials. The azo compound is generally incorporated byblending with granular or powdered plastics material by, for example,dry tumbling or high speed mixing followed by injection moulding on ascrew machine or by conventional compounding/masterbatching techniques.The present dyes generally dissolve or disperse rapidly in hot plasticsmelts and provide bright colorations generally with good clarity andgood light fastness. Plastics which may be coloured in this way includepolystyrene, acrylics, styrene/acrylonitrile mixtures,acrylonitrile/butadiene/styrene mixtures, polycarbonate,polyether-sulphone, nylons, rigid PVC (uPVC) and polypropylene.

The azo compounds of Formula 1 may also be used as colorants for theinks used in solvent-based ink-jet printing processes. These inks,typically based on ketones and/or alcohols, are useful for printing onto hydrophobic substrates such as plastics and metals.

The invention is illustrated but not limited by the following Examplesin which all parts are by weight unless otherwise indicated. All λmaxwere measured in CH₂ Cl₂.

EXAMPLE 1

To a solution of 2,5-dichloro-4-fluorosulphonylaniline (4.9 parts) inacetic acid (30 parts) stirring at ambient temperature, was added asolution of bromine (3.52 parts) in acetic acid (10 parts). The mixturewas stirred for 2 hours at 70° C., cooled to ambient temperature andwater (75 parts) was added. After stirring for 1 hour, the product wasisolated by filtration and dried to yield;6-bromo-2,5-dichloro-4-fluorosulphonylaniline (6.0 parts).

To a mixture of 6-bromo-2,5-dichloro-4-fluorosulphonylaniline (2.6parts) and acetic/propionic acid mixture (15 parts, 86/14 vol/vol),stirring at 0-5° C., was added dropwise nitrosylsulphuric acid solution(5 parts). The mixture was stirred at this temperature for a further 30minutes.

The diazo solution was added slowly to a mixture of N,N-diethylaniline(1.2 parts), methanol (20 parts), water (10 parts) and sulphamic acid(0.5 part), stirring at 0-5° C. After stirring for 3 hours at thistemperature, the product was isolated by filtration, washed with waterand dried to yield4-(6-bromo-2,5-dichloro-4-fluorosulphonylphenylazo)--N,N-diethylaniline(1.3 parts).

When applied to polyester materials from an aqueous dispersion, the dyegives yellow brown shades with excellent light fastness and excellentfastness to wet treatments. λmax=452 nm.

EXAMPLE 2

In place of N,N-diethylaniline (1.2 parts) in Example 1, there were usedN-ethyl-N-(2-cyanoethyl)aniline (1.4 parts) to yield4-(6-bromo-2,5-dichloro4-fluorosulphonylphenylazo)-N-ethyl-N(2-cyanoethyl)aniline (1.6 parts). When applied topolyester materials from an aqueous dispersion, the dye gives yellowbrown shades with excellent light fastness and excellent fastness to wettreatments. λmax=418 nm.

EXAMPLE 3

In place of N,N-diethylaniline (1.2 parts) in Example 1, there were usedN-ethyl-N-(2-ethoxycarbonylethyl)aniline (1.5 parts) to yield4-(6-bromo-2,5-dichloro-4-fluorosulphonylphenylazo)-N-ethyl-N-(2-ethoxycarbonylethyl)aniline(1.4 parts).

When applied to polyester materials from an aqueous dispersion, the dyegives yellow brown shades with excellent light fastness and excellentfastness to wet treatments. λmax=436 nm.

EXAMPLE 4

In place of N,N-diethylaniline (1.2 parts) in Example 1, there were usedN-ethyl-N-(2-acetoxyethyl)aniline (1.4 parts) to yield4-(6-bromo-2,5-dichloro4-fluorosulphonylphenylazo)-N-ethyl-N-(2-acetoxyethyl)aniline(1.3 parts). When applied to polyester materials from an aqueousdispersion, the dye gives yellow brown shades with excellent lightfastness and excellent fastness to wet treatments. λmax=434 nm.

EXAMPLE 5

In place of N,N-diethylaniline (1.2 parts) in Example 1, there were usedN-ethyl-N-(2-phenoxyethyl)aniline (1.7 parts) to yield4-(6-bromo-2,5-dichloro-4-fluorosulphonylphenylazo)--N-ethyl--N-(2-phenoxyethyl)aniline (1.8 parts). When appliedto polyester materials from an aqueous dispersion, the dye gives yellowbrown shades with excellent light fastness and excellent fastness to wettreatments. λmax=446 nm.

I claim:
 1. A monoazo dye which is free from water-solubilizing groupsand has the formula: ##STR5## wherein: Q is --Br or --Cl;R¹ and R² eachindependently is H or is selected from the group consisting of C₁₋₆-alkyl and aryl groups, each of which is optionally substituted by oneor more nonionic substituents; and R³, R⁴ and R⁵ each independently isH, F, Cl, Br, I, --SO₂ F or an organic moiety selected from the groupconsisting of C₁₋₆ -alkyl, C₁₋₆ -alkoxy, C₁₋₄ -alkanoylamino, --NHSO₂alkyl, --NHCOC₁₋₄ alkyl, and -O-phenyl m oieties, each organic moietybeing optionally substituted by one or more nonionic substituents. 2.The monoazo dye according to claim 1, wherein each of R¹ and R²,independently, is C₁₋₆ -alkyl which ioponlysubstituted by one or morenonionic substituents and each of R³, R⁴, R⁵ and R⁶ is H.
 3. The monoazodye according to claim 2, wherein each of R¹ and R² is ethyl which isoptionally substituted by one or more nonionic substituents.
 4. Themonoazo dye according to claim 3, wherein R¹ is --C₂ H₅ ; and R² is --C₂H₄ X, wherein X is selected from the group consisting of --H, --CN,--COOC₂ H₅, --OCOCH₃ and --OC₆ H₅.
 5. A method for the preparation of amonoazo dye according to claim 1 which comprises diazotising6-bromo-2,5-dichloro-4-fluorosulphonylaniline or2,3,6-trichloro-4-fluorosuiphonylaniline and coupling the resultingdiazo compound with an aromatic amine of the formula: ##STR6## whereinR¹ to R⁶ are as defined in claim
 1. 6. A process for coloring asynthetic textile material or a fiber blend thereof which comprisesapplying thereto a monoazo dye according to claim
 1. 7. A process forthe mass coloration of plastic materials, which comprises incorporatinginto a plastics material a monoazo dye according to claim
 1. 8. Themonoazo dye according to claim 1, wherein said non-ionic substituentsfor R¹ to R⁶ are --CN, --OH, OC₁₋₆ alkyl, --OCOC₁₋₆ -alkyl, --COOC₁₋₆-alkyl, phenyl, phenoxy, --OCO-phenyl, --OCO-phenyl-SO₂ F,--O-phenyl-SO₂ F, --CO₂ -phenyl-SO₂ F, --COOC₁₋₆ -alkyl, --OCOC₁₋₆-alkyl, or --COOC₁₋₆ -alkyl-COOC₁₋₆ -alkyl.
 9. The monoazo dye accordingto claim 1, which is4-(6-bromo-2,5-dichloro-4-fluorosulphonylphenylazo)-N,N-diethylaniline.10. The monoazo dye according to claim 1, which is4-(6-bromo-2,5-dichloro-4-fluorosulphonylphenylazo)-N-ethyl-N(2-cyanoethyl)aniline.11. The monoazo dye according to claim 1, which is4-(6-bromo-2,5-dichloro-4-fluorosulphonylphenylazo)-N-ethyl-N-(2-ethoxycarbonylethyl)aniline.12. The monoazo dye according to claim 1, which is4-(6-bromo-2,5-dichloro-4-fluorosulphonylphenylazo)-N-ethyl-N-(2-acetoxyethyl)aniline.13. The monoazo dye according to claim 1, which is4-(6-bromo-2,5-dichloro-4-fluorosulphonylphenylazo)-N-ethyl-N-(2-phenoxyethyl)aniline.14. The process according to claim 5, wherein said diazotizing iseffected in acidic medium with a nitrosating agent at a temperature offrom -10° C. to 10° C.
 15. The process according to claim 5, whereinsaid coupling is effected by adding diazotized6-bromo-2,5-dichloro-4-fluorosulfonylaniline or2,3,6-trichloro-4-fluorosulfonylaniline to the amine of the formula (3)in an alkanol at a temperature of from 0° C. to 10° C.